1. Field of the Invention
The invention relates to a ventilation module optimized as to size and accessibility, and it applies to the field of the air conditioning and the heating of the passenger compartment of motor vehicles.
2. Description of the Related Art
Ventilation is understood to mean the mixing and the circulation of air with a view to obtaining, by coupling with heat exchangers, a fresh air supply, heating or air conditioning for a local area, such as a vehicle passenger compartment.
Ventilation modules are generally arranged under the instrument panel bulkhead of a motor vehicle. They include a molded casing having at least one air-inlet entry and an air-outlet exit towards the passenger compartment to be heated or to be cooled. Between the air entry and exit, the casing houses an air blower including an assembly called motorized fan unit (MFU for short), an air-intake flap, and a shell encasing the MFU unit and conducting the air, sucked in and blown by the turbine, from the entry to the exit of the casing.
The MFU unit itself consists of an air-suction turbine, of an electric motor for driving the turbine, and of a motor support coupled to a shroud serving as a seating for the turbine. The incoming air is sucked in by the turbine through at least one central orifice formed in the shell and defined by the edges of the shroud. When the MFU is a double-suction type, two orifices are provided: an upper orifice formed above the vanes and a lower orifice formed around the motor.
In the ventilation modules for air conditioning/heating, an air-intake flap is generally provided, allowing for admission of a single suction of air originating from an external source, or a double suction, either of outside air or of recycled air originating from the passenger compartment.
The air-intake flap is conventionally arranged above the shell. It is flat and tilts between two positions, an opening position and a closing position for one and/or the other of the air intakes. This flap is called butterfly flap or flag flap depending on the position of its axis of rotation, central or lateral.
However, this type of flap exhibits the major drawback of using up a significant amount of space in an environment where size is a critical parameter. Moreover, it limits the air-intake passage cross section and does not optimize the orientation of the suctions of air into the shell, in particular in the double-suction layout.
The present invention aims to resolve these problems by proposing to produce the module in such a way that the flap features an axis of rotation which is substantially parallel to the suction turbine(s).
More precisely, the subject of the invention is a one-piece ventilation module optimized as to size, accessibility and air circulation, consisting of a shell housing accommodating an MFU unit, an inlet flap for letting air into the turbine and means for actuating the flap, the MFU unit comprising at least one turbine driven in rotation by an electric motor about a central rotational axis, the shell being coupled to at least one air intake and outlet formed in an outer housing, the incoming air being sucked in by the turbine through at least one central orifice formed in the shell, and in which the air-inlet flap extends on either side of the shell and is driven in rotation by the actuating means about an axis passing through the space delimited by the housing of the shell parallel to the rotational axis of the turbine(s).
According to one particular embodiment, the air-inlet flap includes a cylindrical dome parallel to the rotational axis of the turbines, terminated along this axis by two circular sectors which are articulated onto this axis, and two peripheral overshoots parallel to this axis bearing on end stops arising from the outer casing.
According to preferred characteristics:
the actuator drives the flap into intermediate or extreme positions between, on the one hand, a position freeing the outside-air intake and closing a recycled-air intake and, on the other hand, a position closing the outside-air intake and freeing the recycled-air intake, the intermediate positions making it possible to carry out partial recycling of the air;
the outside-air and recycled-air intakes exhibit shapes matching those of the flap in order to make them leaktight when they are closed by the flap;
the rotational axis of the flap passes through the shell orifice; in particular, it is coincident with the rotational axis of the turbine;
the actuator for driving the flap includes a pinion coupled to a micromotor, the pinion and the micromotor being mounted centrally with respect to the flap; this central drive avoids the creation of torsion from the flap on the pinion, which increases the reliability and the leaktightness of the layout;
the drive actuator also comprises a guide roller in order to prevent the flap escaping from the drive pinion;
According to particular embodiments, the shapes of the flap and of the housing are matched so as to allow the use of movements freeing an exit space which can be used for removing/fitting the MFU. According to advantageous characteristics:
the housing and the flap exhibit a frustoconical shape in a so-called upper part, opposite the exit space from the MFU, and a cylindrical lower part on the same side as the exit space, the two parts of the housing being detachable from one another via releasable means;
the module being of the double-suction type, the housing featuring detachable parts, in particular two half-housings, and the shell and the flap featuring lateral flanks, the dimensions of the air-passage orifice of the bottom of the shell, the difference in dimensions between the shell flanks and the flap, and the difference in dimensions between the junction of the two half-housings which is situated at the opposite end to the flap and the bottom of the flap once the lower part of the housing has been withdrawn and the flap translated along its axis coincident with the axis of the turbine, are set so as to clear an exit space which can be used for removing/fitting the MFU;
the junction between the two parts of the housing situated at the opposite end from the flap is set just above the shell in order to allow withdrawal by translation of the MFU through the exit space created after withdrawing the lower housing part;
a particular shape of the dome in a hollow, featuring a discontinuity or an indentation parallel to the rotational axis of the turbine, and/or an offset of the amplitude ranges of the flap, and/or a housing overshoot, create a space for removal by rotation of the flap about an axis parallel to the rotational axis of the turbine arranged close to one range end stop;
the flap is produced in two detachable parts, an upper part possibly being conical, arranged at the opposite end to the exit space, and a lower part on the same side as the exit space, the lower part being detached in order to free the space which can be used for removing the MFU.
The invention applies as much to light vehicles as to heavy good vehicles. In this latter case, it is advantageous to provide for the MFU unit to be removed from the engine compartment after the driver""s cab been tilted. The ventilation module includes a fixed mechanism plate, which is docked into an aperture of the engine compartment, a flap of the preceding type, flap rotational support means, a means for electrically driving the flap, a removable shell housing and an MFU unit.
The essential functions of ventilation are thus brought together onto a single independent and removable module the settings of which are preserved, which facilitates maintenance and reliability. The MFU unit forms a subassembly mounted in the module via releasable means, independently of the other components, for example by a fixing collar.
According to particular embodiments, the electric drive means is a micromotor arranged in the central part on the removable housing of a double shell symmetrically accommodating two turbines. This central layout makes it possible to avoid torsion of the flap and the additional stiffening means usually used.
This micromotor may advantageously drive the flap by the use of a pinion-type transmission, the pinion possibly being extended by a roller guided in the groove, and the MFU unit is preferably fixed by a removable collar around the motor ring screwed onto the shell housing.
Other characteristics and advantages of the invention will emerge on reading the description which follows relating to exemplary embodiments, by reference to the attached figures which respectively represent: